Automatic lattice fabrication apparatus

ABSTRACT

This invention relates to automatic lattice fabrication apparatus for automatically forming sections of lattice from strips of wood of a predetermined length and width. The apparatus includes an elongated horizontal conveyor that conveys lattice strips from a lay-up section through an automatic adhesive dispenser, under an automatic stapling bridge where the lattice is stapled, through rip saws that trim the sides of the lattice and, when desired, cut the lattice in half, and through an automatic cross-cut saw mechanism that periodically stops the conveyor, lowers a saw and cuts off a section of lattice when it reaches a predetermined length, and then lifts the saw out of the way and resumes conveyor movement.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of applicants' copending patent application. Ser.No. 623,975, filed June 25, 1984 for AUTOMATIC LATTICE FABRICATIONAPPARATUS, U.S. Pat. No. 4,569,949, issued Jan. 7, 1986.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an automatic lattice fabrication apparatus forautomatically forming sections of lattice work formed of criss-crossedstrips of wood of a pre-determined length and width.

2. Description of Prior Art

Lattice is formed typically of criss-crossed thin strips of wood("lattice strips") that are glued or stapled together to form an openscreen with square or rectangular holes through the lattice pattern.Lattice is sometimes used as indoor wall paneling but generally is usedfor a variety of outdoor purposes, including gardening or the like forpurposes of supporting climbing plants.

At the present time, a lattice is generally formed by hand on a table,with strips of wood being laid in a criss-crossed pattern, gluedtogether and stapled by hand. The lattice is then trimmed to its propersize with a hand or power saw. This operation is slow and expensive andinvolves a substantial amount of labor.

An object of the present invention is to provide automated machinery forautomatically fabricating high quality lattice structure with a minimumlabor requirement.

SUMMARY OF THE INVENTION

In accordance with the present invention, an automatic latticefabricating machine is mounted on an elongated frame. An elongatedhorizontal conveyor is mounted on the frame and has position locatingmeans thereon for positioning strips of wood in a criss-crossed patternto form a lattice structure, the conveyor having a lattice lay-upsection at an upstream portion of the conveyor, wherein lattice stripsare laid in the proper position on the conveyor. An automatic staplingapparatus downstream of the lay-up section includes a plurality ofstapling guns mounted transversely on a bridge extending over theconveyor. The stapling guns are movably mounted on a mounting mechanismfor vertical movement. The stapling guns include ramps upstream of thestapling guns that engage the lattice as it approaches the head of thestapling guns and urge the stapler heads upwardly so that the latticecan pass under the stapler heads in proper position for stapling. Acontrol mechanism actuates the stapler guns whenever the intersectionsof the wood strips are properly positioned under the stapler heads,preferably stopping the conveyor briefly during stapling. Rip sawsdownstream of the stapler apparatus automatically trim the sides of thelattice at each side of the frame. An automatic cross-cut saw positionedon a bridge downstream of the stapler automatically cuts the latticeinto sections. The saw is transversely and vertically movable so that itautomatically lowers into position and moves transversely to cut thelattice into sections and then raises upwardly out of the plane of thelattice. The control mechanism stops the conveyor while the lattice isbeing cut into sections in this manner.

An important feature of the present invention is the manner in which thestapler guns are mounted. The stapler guns have stapler heads at anupstream end with stapler cartridges extending horizontally away fromthe heads in a downstream direction along the conveyor. The staplers aremounted on pivoting or parallelogram linkage that lets the stapler headmove upwardly to accommodate different thicknesses of lattice. Thispermits proper positioning of the stapler head over each intersectinglattice strip without requiring strips of uniform fitness or precisepositioning of the stapler head.

In the present invention, the cross-cut saw is mounted on a separateframe and operated by a hydraulic motor. Pneumatic cylinders pivot thecross-cut saw upwardly and downwardly about a pivoted carriage member inorder to bring it in contact with the lattice work passing thereunder.The saw carriage member is transversely movable under hydraulic forcealong a bridge over the frame.

An additional feature of the present invention is a pneumaticallyoperated automatic adhesive dispenser mechanism that includes a pair ofautomatic adhesive dispensers mounted on opposite sides of the frame ona bridge that extends over the conveyor. The control mechanism causesthe adhesive to be dispensed whenever a wood strip is properlypositioned below the dispenser nozzle.

The control mechanism preferably is an electronic controller butconventional relay timing circuits will work. Timing is provided by alimit switch that senses each section of conveyor by means of conveyortiming blocks mounted on the underside of the conveyor.

The present invention provides a simple and effective machine forautomatically fabricating high quality lattice using a minimum amount oflabor.

These and other features and advantages of the present invention will bedescribed in more detail below in connection with a description of thepreferred embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an automatic lattice fabricating machineconstructed in accordance with the present invention.

FIG. 2 is a side elevational view of the machine of FIG. 1.

FIG. 3 is a ectional view taken along line 3--3 of FIG. 2.

FIG. 4 is a partial plan view of the lattice fabricating machine showingthe manner in which the pneumatic stapler guns are mounted over theconveyor assembly.

FIG. 5 is a view taken along line 5--5 of FIG. 4.

FIG. 6 is an alternative embodiment of a mounting mechanism pneumaticstapler guns.

FIG. 7 is a view taken along line 7--7 of FIG. 5, showing a plan view ofone stapler gun mounted over the conveyor.

FIG. 8 is a simplfied perspective view of the stapling mechanism of thepresent invention.

FIG. 9 is a perspective view of the automatic cross-cut saw of thepresent invention.

FIG. 10 is an end view of the cross-cut saw mechanism of the presentinvention.

FIG. 11 is an exploded view of the movable frame mechanism for thecross-cut saw.

FIG. 12 is a hydraulic schematic diagram of the present invention.

FIG. 13 is an electrical schematic diagram of the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring to the drawings, and more particularly to FIG. 1, a latticefabricating machine 10 constructed in accordance with the presentinvention makes it possible to construct lattice automatically andcontinuously in appropriately sized sections with a minimum of labor.The lattice fabricating machine comprises an elongated table or frame 12with a slat conveyor 14 moving continuously along the frame from anupstream end to a donwstream end. The upstream end of the conveyorcomprises a lay-up portion 20 of the machine, wherein lattice strips 16are first laid on the moving conveyor in one diagonal direction and thenlattice strips 16' are laid in a diagonally opposite direction on top ofthe lattice strips 16 and spaced apart to form a lattice type offramework. The strips can be glued at the lay-up section 20 by means ofan automatic glue dispensing mechanism 22.

After the lattice work has been placed in proper position, the latticeis automatically stapled together by means of a novel pneumatic staplingmechanism 24. The sides of the lattice are then trimmed by means ofelectrically powered rip saws 26 at opposite sides of the frame. Thelattice then passes through an automatic cross-cut saw mechanism 28 andon to a table 30 at the downstream end of the mechanism. When the end ofthe lattice strikes a limit switch 32 at the end of the table, theconveyor mechanism is stopped and the cross-cut saw is actuated todescend downwardly and transversely so as to cut the downstream sectionof lattice off. The lattice is then removed and the conveyorautomatically reactuated to continue the operation of the machine.

The details of the individual components of the machine and the overalloperation of the machine are described in more detail below.

Referring to FIGS. 2 and 3, the frame and conveyor assembly are shown inmore detail. Frame 12 comprises horizontal side rails 34 and supportinglegs 36 extending downwardly from the side rails to the ground. Lowerside rails 38 are positioned between upper side rails 34 and the groundand support the slat conveyor on its return path. Cross members 39support side rails 38.

Slat conveyor 14 is a conventional slat conveyor in most respects,comprising a plurality of closely spaced slats 40 (FIG. 1) extendingbetween endless loop linked drive chains 42 interconnecting theundersides of the slats on opposite sides of the frame (FIG. 3). Thedrive chains ride on sprockets 44 at the upstream end of the frame anddrive sprockets 46 at the downstream end of the frame. The downstreamsprockets are driven by a hydraulic motor 48 through a chain drive 49,in which the power for which is provided by a hydraulic power unit 50(FIG. 1). The hydraulic power unit drives the conveyor and the cross-cutsaw carriage drive motor through hydraulic lines 52 to and from theconveyor drive motor and lines 54 to and from the carriage drive motor.

The upper surfaces of the individual slats in the slat bed conveyorinclude upwardly protruding dowels 52, which are positioned to assist inlocating the lattice strips in their proper positions on the flat bedconveyor. With the dowels on opposite sides of the slat bed conveyor,the lattice strips are placed between the dowels and automatically arepositioned in their correct positions.

The timing of all of the operations of the present mechanism iscontrolled by means of conveyor timing blocks 54 on the undersides ofthe slats of the slat bed conveyor. These timing blocks are shownprotruding upwardly on the return loop of the slats adjacent rail 38, asshown in FIGS. 1 and 2. The timing blocks come in contact with a limitswitch 56 positioned adjacent the underside of the conveyor as they passin their forward path. A control signal is thus actuated each time aslat occupies a predetermined position in the loop. This timing signalis transmitted to a control mechanism 58 which controls the actuationand timing of the various operations in the apparatus.

In order to provide proper adjustment of the tension of the slatconveyor, a slat take-up mechanism 60 is positioned at the upper end ofthe conveyor. This mechanism comprises frames 62 positioned on each sideof the framework in which axles 64 of the upstream sprockets aremounted. Frames 62 can be moved in an upstream or downstream directionby means of rotatable drive screws 66 drivingly attached to frames 62.Rotation of the drive screws through bolts 68 which are held in a fixedaxial position by means of brackets 70 causes the frames 62 and theattached sprockets to be moved in an upstream or downstream direction.

As discussed above, in assembling the lattice, diagonal strips 16 arefirst laid on the slat conveyor at the upstream end of the conveyor.These lattice strips then pass under an automatic adhesive dispensermechanism 22 mounted on a bridge 72 that extends across the conveyor.Bridge 72 is mounted on a side frame 74 that is spaced outwardly fromthe frame of the conveyor mechanism a sufficient distance to let theuntrimmed ends of the lattice strips pass under the bridge of theadhesive dispenser mechanism. A pair of adhesive dispenser nozzles 76are mounted on opposite sides of the bridge 72 and connected to astorage container 78 that can contain up to about five gallons ofadhesive. A conduit tube 80 interconnects the storage container and theadhesive dispenser nozzles. Adhesive is pumped from the storagecontainer to the adhesive dispenser nozzles by means of a pneumatic pump82. The adhesive dispenser nozzles can be acuated by controller 58(which can be a conventional electronic controller) or they can beactuated by physical contact between the nozzles and the strips passingunderneath the nozzles. The automatic dispensation of adhesive on thestrips is a desirable feature of the present apparatus.

After the first strips 16 have been laid in place and any adhesiveapplied to the strips, the second strips 16' are then manually laid inplace with the positioning dowels serving to properly locate the strips.

The conveyor then conveys the properly located strips to staplingmechanism 24. Stapling mechanism 24, as shown in some detail in FIGS.4-8, comprises a bridge 84 formed of right angle iron or the like thatextends across the conveyor at a position above the lattice strips. Theends of bridge 84 are attached to a side frame 86 that is spacedoutwardly from the side of the conveyor frame at sufficient distance tolet the untrimmed ends of the lattice strips pass by the frame under thebridge. Frame 86 includes leg 88 extending downwardly from bridge 84 andconnected to frame 12 by means of an upper horizontal arm 90 and a lowerhorizontal arm 92 extending inwardly to a vertical leg 93 extendingbetween side rails 34 and 38.

An air manifold 94 is mounted between the legs of right angle bridge 84and comprises a cylindrical closed tubular member. A transverse supportmember in the form of a generally U-shaped channel 96 with an open sidefacing in a downstream direction is attached to the upper leg 97 ofbridge 84. U-shaped channel 96 extends transversely over the entirewidth of the conveyor mechanism. A plurality of staple guns 100 arereleasably mounted side by side in the channel mounting mechanism.Staple guns 100 have staple heads 98 at an upstream end of the stapleguns and have staple cartridges 102 extending longitudinally in adownstream direction. The staple heads are oriented side by side so thatthe staples are injected into the lattice in a plane transverse to thedirection of movement of the conveyor.

Each staple gun 100 is attached to channel 96 by means of a movablemounting bracket 104 that permits upward and downward movement of thestaple gun. The upward and downward movement of the staple gun isessential to accommodate lattice strips of different thicknesses so thatthe staple gun can always be properly positioned on the upper surface oftwo lattice strips that are to be stapled together. The mounting bracket104 comprises an outer stapling gun support member and an inner retainer114. The support member, shown in FIG. 5, preferably is a parallelogramlinkage comprising parallel, horizontal mounting arms 106 spacedvertically apart and pivotably mounted at one end to a vertical arm 108extending upwardly from a plate 109 on the top of the staple gun and atanother end to a vertical mounting member 110. Mounting member 110 is inturn releasably attached to U-shaped channel 96 by means of threadedfastener 112 that extends through mounting member 110 into a threadedopening in retainer 114 positioned on the inside of the U-shapedchannel. Inwardly extending and hooked flanges 116 on the open ends ofthe channel engage corresponding gooves in the retainer to hold theretainer within the channel and thus serve as a means for locking themounting brackets in any given position in the channel. The transverseposition of a stapler gun can be varied by loosening threaded fastener112 and sliding the mounting bracket in a transverse position to itsproper location. Also, the width of the retainer is less than the heightof the opening so that the staple gun and retainer can easily be removedby loosening fastener 112, turning the retainer sideways in the channel(2 opposite corners of the retainer can be rounded off to facilitatethis pivoting movement), and sliding the retainer out through theopening in the channel.

In the preferred practice of the present invention, channel 96 andretainer 114 are commercially available as a mounting unit. These aresold under the brand names Unistrut and Globestrut.

As shown in FIG. 7, the parallelogram links 106 are positioned on bothsides of member 108 and are pivotably mounted to that member by means ofbolts or axles 117 that extend through member 108. Similarly, the otherends of arms 106 are mounted on opposite sides of mounting member 110 bymeans of bolts or axles 122 that extend through the mounting member. Acentral opening in the mounting member accepts the threaded fastener 112in order to attach the mounting member to the transverse U-shapedchannel 96.

The lay-out of the individual stapler heads is shown in FIG. 4. Asindicated, these stapler heads are immediately adjacent and very closeto each other, so that all of the overlapping joints of the lattice canbe stapled together. The stapler guns on the outer ends of the bridgeare positioned in transverse orientation, as shown by the position ofstapler gun 100' in FIG. 4, so that the end staples are orientedlongitudinally. This permits the rip saws to trim the lattice withoutrunning into the staples.

Another type of mounting mechanism for the staple guns is shown in FIG.6. In this mechanism, the same angle iron bridge 84 and same airmanifold 94 are employed. Also, the same U-shaped channel 96 andretainer 114 are employed. The main difference is the mounting mechanismfor mounting the staple guns to the U-shaped channel mechanism. In thisembodiment, this is accomplished by a support member 118 that isattached by a fastener 119 to the U-shaped channel member 96 by means ofretainer 114. Member 118 comprises mounting flange 121 that abuts thechannel 96, a vertical plate 123 extending downstream therefrom and ahorizontal plate 126 extending perpendicularly thereto. A pair of spacedbosses 128 extend downwardly from the underside of plate 126. A boss 129extends upwardly from a plate 124 on the top of the staple gun and fitsbetween bosses 128. A transverse bolt or axle 130 extends throughaligned openings in the bosses 128 and through an opening in boss 129,pivotably mounting the staple gun 100 on the bosses 128 so that the guncan pivot in an upwardly direction as shown by phantom FIG. 100' in FIG.6.

The difference in operation of the stapler mechanism of FIG. 6 and themechanism of FIG. 5 is that when lattice passes underneath the staplemechanism of FIG. 6, the staple guns pivot as opposed to raisingdirectly upwardly. The angle of the staples thus change with therotation of the staple gun in FIG. 6. This can cause injection ofstaples at different angles and positions for different thicknesses oflattice. A wide variation in the angle of the staples is not expected sothe variation usually does not cause any significant problems.Nonetheless, the parallelogram linkage has a straight vertical movementand is thus preferred.

As stated above, the staple guns are operated pneumatically through airmanifold 94, which receives pressurized air from a source throughconduit 230. Pressurized air is conveyed from the air manifold throughindividual staple gun outlets 134 spaced along the length of manifold94. Fittings 135 interconnect the outlets with conduits 136 leading fromfittings 135 to the staple gun, where quick release fittings 137 areemployed. For clarity, only one of the conduits is shown in thedrawings. Thus, the staple guns can be disconnected from their pneunaticconnections easily for removal and disassembly.

The triggering of the staple guns is accomplished by an air triggercontrol mechanism 138 (FIG. 6). The air trigger mechanism has a separateair supply inlet conduit 232 and a separate solenoid valve 236 forcontrolling operation and has separate outlets 139 connected throughfittings 141 (FIG. 6) to individual conduits 140 that lead to quickrelease trigger fittings 142 on the staple guns. The staple guns areactuated by the electronic controller.

The lower end of each staple gun comprises a deflector plate 144, whichis a horizontally positioned plate or rail or shoe with a upwardlycurved end facing upstream from the staple gun. These deflector platesengage the lattice strips as they approach the staple gun and direct thelattice strips underneath the heads of the staple guns, serving as camsto urge the staple guns to move and make room for the lattice strips topass under.

After the lattice strips have been stapled together by the staplingmechanism, they are ready to be cut into sections of predeterminedsizes. Rip saws 26 mounted at opposite sides of a rip saw frame 145 atthe end of frame 12 trim the lattice to its desired width. Typicallythis is a four foot wide section. Each rip saw is operated by a separateelectric drive motor 146 (FIG. 2) through an appropriate belt drive 148,through axles 150. As another feature, the apparatus can include anauxillary center saw 152 that can be raised or lowered as desired. Inthe illustration in FIG. 3, saw 152 is mounted on one end of a plate 163that is pivotably mounted on the frame at the other end by bosses 165.An air cylinder 167 mounted on a bracket 169 raises and lowers the plateby pivoting it up and down. When raised, saw 152 will cut the latticepanel into two sections each two feet wide. This saw is powered by aseparate hydraulic motor 153 through belt drive 155 and able 157.

As the sections with their trimmed sides continue to pass along theframework, they are pushed through the cross-cut saw mechanism 28 and onto a take-off table 30. When a section of lattice contacts limit switch32, the limit switch sends a signal to controller 58, and the conveyoris stopped. At this point, a saw 154 in cross-cut saw mechanism 28 islowered and actuated and moved transversely across the lattice to cutthe lattice section off.

The cross-cut saw mechanism 28 is shown in detail in FIGS. 9-11.Cross-cut saw mechanism 28 is a separate module and includes a frame 156positioned immediately adjacent to downstream end of frame 145. Frames145 and 156 could be an extension of frame 12 but are preferablyseparate in the present invention. This permits easy removal of the sawmechanisms for repair or the like. Frame 156 comprises a rectangularupper box member 158 with legs 160 at the corners. A pair of spacedplates 198 extend between the sides of the box member below saw blade154 and serve as support for the lattice as the saw cuts the lattice andfits in the space between the plates. A reinforcing box member 162 ispositioned below box frame 158. An upper frame or bridge assembly 168comprising upwardly extending legs 170 and transverse parallel rails 172extending over box member 158. Rails 172 have vertical side edges 174and inwardly extending horizontal flanges 176.

A carriage 178 having rotating wheels 180 on vertical sides 182 thereof(FIG. 11) rides between rails 172, with wheels 180 riding on flanges176. A lower wheel 184 on the side of carriage 178 rides on theunderside of each flange 176 at each side of the carriage. A flat plate186 extends between sides 182 of the carriage. A chain 188 extends froma mounting block 190 on each end of the carriage and around a rotatingsprocket 192 at one end of the frame and 194 at the other end of theframe, with the sprockets being rotatably mounted on axles extendingbetween sides 174 of the frame. A reversible direction hydraulic motor164 drives sprocket 192. When the motor turns sprocket 192 in eitherdirection, the carriage is driven one way or the other along the trackformed by inwardly extending flanges 176. This moves the saw back andforth transversely across the width of the frame. Carriage 178 has anL-shaped saw mounting frame 202 pivotably mounted between bosses 204extending downwardly from the underside of the carriage. Mounting frame202 includes upwardly extending legs 206 having openings 208 thereinthat receive axles or bolts through corresponding openings 210 in bosses204. An electric saw drive motor 212 is mounted on a mounting plate 214attached to lower side rails 216 of the motor mounting frame. Motor 212drives saw axle 218 (the saw being removed to make the illustration moreclear) by means of drive sprockets acting through a chain 220.

The saw is raised and lowered on the carriage by means of a pneumaticair cylinder 222 extending from a pivotable mounting boss 224 on theunderside of the carriage to the pivotable mounting boss 226 on thelower left end (FIG. 11) of the L-shaped mounting frame. Boss 226 ismounted on a cross member 228 extending between the outer ends of rails216. Air cylinder 222 is pneumatically acutated by solenoid 244, whichdrives the air cylinder through conduits 230 by means of a source of airpressure. An upwardly extending support frame 231 holds the air hosesabove the track and permits transverse movement of the carriage.

Whenever the control mechanism actuates the solenoid 244, air cylinder222 extends and pivots the saw motor downwardly about a pivot axisextending through openings 208 in the mounting frame to the loweredposition 202'0 shown in phantom in FIG. 10.

In operation, whenever limit switch 32 is actuated, controller 58actuates solenoid 244 (FIG. 12), which extends air cylinder 222 to lowerthe cross cut saw (which operates continuously). The carriage drivemotor also is actuated to move the carriage frame from one side of theframe to the other, thus cutting the lattice panel from the upstreamweb. The controller also actuates a conveyor drive solenoid 233 (FIG. 1)that stops the conveyor.

When the carriage reaches the end of its track, it engages a limitswitch 181, and this causes the controller 58 to reverse the directionof the carriage drive motor through a double acting solenoid 183(FIG. 1) and return the carriage to its original position. At the sametime, the controller causes solenoid 244 to retract air cylinder 222 toraise the cross-cut saw out of the path of the lattice. When a completedlattice panel is removed from the table at the end of the apparatus,limit switch 32 is de-energized, and this causes the controller toreactuate the conveyor drive motor through conveyor drive solenoid 233.Typically the delay is about five seconds for the cross-cut sawoperation.

A diagram of the pneumatic circuitry is shown in FIG. 12. Pressurizedair preferably at 150 psi is provided from a conventional source 210through a one inch pipe 212 and through a filter 214, a regulator 216,and a lubricator unit 218. The air pressure is then transmitted througha fitting 220 to a conduit 221 leading to two standard hand held stapleguns 224. These are used on the table 30 at the end of the apparatus formanually repairing panels as needed. Conduit 221 also leads to aseparate conduit 226 that conveys pressurized air to the adhesive pumpair supply. Another conduit 228 leading from fitting 220 conveyspressurized air through a one inch pipe to staple gun driver manifold 94and to air trigger manifold 138. Conduit 230 leads to the staple gundriver manifold and conduit 232 leads to air trigger manifold 138through pressure regulator 234 and solenoid 236 with a back pressurerelief outlet 238.

The preferred staple guns 100 of the present invention are manufacturedby Senco Fastening Systems and sold as tool numbers LN3045. They have anoutward flair guide body the double length magazine and are actuated byan air trigger.

Staple gun driver manifold 94 is provided with a drain valve 239.

A third line 240 exiting from fitting 220 leads through a fitting 260 tothe raising and lowering apparatus of the cross-cut saw mechanism. Line240 leads through a pressure regulator 242 to a solenoid 244. This valvedirects air pressure to either end of cylinder 222 through lines 246 or248 to lower and raise the saw blade, respectively.

Line 262 leads through pressure regulator 264 and a solenoid 266 to aircylinder 167 that raises and lowers platform 163 for saw 152.

An electrical schematic diagram of the present invention is shown inFIG. 13. Limit switch LSl (limit switch 56) senses the point at whichthe staple guns should fire. When this occurs, the control mechanismenergizes timing delay TDl, which stops the conveyor for about onesecond. At the same time, timing delay TDl causes timing delay TDIA tofire the staple guns after a delay of 0.1 to 0.5 seconds. Thus, there isa slight delay in conveyor movement just before and just after thestaples are fired. This slight delay in the conveyor movement ensuresthat the staples are properly driven into the lattice strips. TDl thenbypasses limit switch LS1 and the conveyor starts up again.

Limit switch LS2 (limit switch 32) senses the panel cut-off length anddisables the conveyor drive when actuated. It also enables the cut-offsaw lowering solenoid 244 to extend air cylinder 222 and lower the saw.Finally, it enables the carriage drive solenoid 183, which causes thecarriage to move across the frame.

Limit switch LS3 (limit switch 181) senses when the cut is completed andreverses the carriage drive solenoid and disables the saw loweringsolenoid so that the saw is retracted and transferred transversely toits starting position. Removal of the completed panel de-energizes limitswitch LS2 (switch 32) and resumes the conveyor drive.

It should be understood that the foregoing represents a description of apreferred embodiment of the present invention and that various changesand modification may be made in the arrangements and details ofconstruction of these embodiments without departing from the spirit andscope of the present invention as defined in the appended claims.

We claim:
 1. Lattice fabrication apparatus for forming lattice stripscomprising:an elongated frame; an elongated conveyor positioned on theframe and having a generally horizontal conveying surface thereon, theconveyor having positioning means thereof for positioning the latticestrips in their desired overlapping position, the conveyor having alattice lay-up portion at an upstream position of the conveyor;automatic stapling apparatus positioned downstream of the lay-upportion, the stapling apparatus comprising a series of staple gunsmounted across the conveyor so as to be in alignment with theoverlapping portions of the lattice as they pass by the staple guns;longitudinally oriented powered rip saws positioned downstream of thestapling apparatus on the sides of the frame that trim excess latticefrom the sides of the lattice; a cross-cut saw mechanism positioneddownstream of the stapling apparatus and aligned for receipt of stapledlattice, said cross-cut saw mechanism ordinarily permitting the latticeto pass unimpeded therethrough but being activated to cut off a sectionof lattice when the section of lattice passing through the cross-cut sawmechanism reaches a predetermined length, the cross-cut saw mechanismthereafter becoming deactivated and permitting resumption of unimpededtransfer of lattice through the apparatus; and control means for sensinglattice position and automatically actuating the staple guns when theoverlapping lattice strips are properly positioned adjacent the guns,the control means sensing lattice section length and automaticallyactuating the cross-cut saw mechanism to cut off the lattice when eachsection reaches a predetermined length, the control means actuating thecross-cut saw and moving the cross-cut saw into engagement with thelattice to cut the lattice at said predetermined length and thereaftermoving the cross-cut saw out ot engagement with the lattice. 2.Apparatus according to claim 1 and further comprising automatic adhesivedispenser means for dispensing adhesive on lattice strips as they areconveyed along the conveyor before overlapping strips are placed thereonand at locations where the strips will overlap.
 3. Apparatus accordingto claim 1 wherein the stapling apparatus is mounted adjacent theconveyor on at least one staple bridge extending across the conveyor,the staple guns being mounted on the bridge by stapler mounting meansthat permit sideways position adjustment of the staple guns on thestaple bridge.
 4. Apparatus according to claim 3 wherein the staplermounting means comprises a transverse support member on the bridge andindividual mounting brackets mounted on each staple gun, the mountingbrackets interfitting with the transverse support to suspend the stapleguns from the transverse support, the mounting brackets being slidabletransversely along the transverse support, the mounting means furtherincluding releasable fastener means for each mounting bracket forlocking each staple gun in its desired lateral position on thetransverse support, the fastener means being releasable for movement ordismounting of the staple guns.
 5. Apparatus according to claim 4wherein the transverse support member is a channel member with an openinterior, an elongated opening on one side, and inwardly extendingflanges partially covering the opening on each side of the opening, themounting bracket for each staple gun comprising a retainer having athreaded opening therein fitting behind the flanges and sliding alongthe interior of the channel, the mounting bracket comprising a staplegun support to which the staple gun is attached, the staple gun supportbeing positioned adjacent to the retainer outside of the channel, thestaple gun support holding a threaded fastener that engages theretainer, tightening of the threaded fastener in the retainer serving tolock the staple gun support in its transverse position on the channel,the staple gun support permitting vertical movement of the staple gunwith respect to the transverse support member.
 6. Apparatus according toclaim 1 wherein the stapling apparatus includes stapler mounting meansfor movably mounting the staple guns for at least partially verticalmovement in response to movement of the overlapped portions of thelattice strips past the staple guns.
 7. Apparatus according to claim 6and further comprising ramp means facing upstream from the staple gunsfor guiding the overlapping lattice strips into vertical alignment withthe staple guns and urging the stapler guns to move vertically to permitthe lattice to pass by the staple guns.
 8. Apparatus according to claim6 wherein the stapler mounting means comprises a pivotable parallelogramlinkage interconnecting each staple gun with the bridge, theparallelogram linkage constraining the movement of each staple gun to agenerally vertical movement.
 9. Apparatus according to claim 6 whereinthe stapler mounting means comprises a pivot mechanism pivotablyconnecting each staple gun to the bridge, the pivot mechanismconstraining movement of the staple gun to a pivotable movement about atransverse axis.
 10. Apparatus according to claim 9 wherein the stapleguns comprise stapling heads that face upstream so as to inject staplesthat are oriented transversely, the staple guns having horizontallydisposed staple cartridges that extend downstream from the staplingheads, the stapling heads being attached to the stapler mounting means.11. Apparatus according to claim 1 and further comprising means forengaging the overlapped lattice strips and resiliently urging themtogether as they move past the stapler guns.
 12. Apparatus according toclaim 1 wherein the cross-cut saw mechanism ordinarily permits thelattice to pass unimpeded therethrough but is resonsive to the length ofsaid lattice to automatically stop the lattice and conveyor when asection of lattice passing through the cross-cut saw mechanism reaches apredetermined length, the cross-cut saw mechanism thereafter cutting offsaid section and then resuming transfer of lattice through theapparatus.
 13. Apparatus according to claim 12 wherein the cross-cut sawmeans comprises:a frame having a generally horizontal lower portion thatreceives and supports lattice for movement over the lower portion afterit has been stapled, the frame also including an upper portion extendingover the lower portion and including a transverse track running in atransverse path plane parallel to the lower portion; a carriage movablymounted for transverse movement on the track; transverse drive means forautomatically moving the carriage back and forth on the track uponactuation; a saw mounting frame positioned below the carriage andpivotably attached at one end to the underside of the carriage fordownward and upward movement of the other end of the frame. atransversely positioned cross-cut saw and motor therefor mounted on themounting frame and being movable downwardly and upwardly by pivotalmovement of the frame, the saw being positioned such that it intersectsthe lattice when it is lowered; and lifting means for automaticallylowering and raising the saw frame on actuation.
 14. Apparatus accordingto claim wherein the rip saws include a pair of side rip saws onopposite sides of the frame and a central rip saw positioned between theside rip saws, the central rip saw being raisable to cut the latticeinto multiple side-by-side sections or lowerable out of the path of thelattice to leave the lattice as a single elongated section. 15.Apparatus according to claim 1 wherein the control means stops theconveyor while the staple guns are being actuated.